The Russian Prime Minister, Mikhail Fradkov, has called for tougher safety measures after one of the country's worst mine accidents in a generation.

It appears most of the Ulyanovskaya mine's management was underground at the time of the explosion, which left more than 100 people dead.

Coal mining is an inherently dangerous activity.

But Russia and other former Soviet republics have a particularly poor safety record.

Statistically, the region comes second only to China in terms of annual fatalities.

Soviet-era problems

Russia is thought to be the fifth biggest producer of coal in the world, and to have the world's second largest reserves.

Coal mining remains an important industry, even if the total number of working mines has declined sharply since 1988, when the Soviet coal industry reached its peak output.

When the sector embarked upon serious reform, after the collapse of the USSR in 1991, most of the mines were already at least 40 years old.

Many dated back to the 1930s, opened in the Stalinist drive for industrialisation and energy, a process in which human life was expendable.

Mining deaths in Russia reached their peak in the late 1990s. A lack of funds led to antiquated equipment not being repaired, and to managers failing to provide for even a minimum of safety standards.

Methane detectors, for example, were simply not available in many mines.

The sector was plagued by wage arrears, sparking off frequent strikes. Miners are a potent political force in Russia and Ukraine, and officials usually moved quickly to assuage their demands.

Kemerovo region, where Ulyanovskaya is located, was the testing ground for mine privatisation in Russia.

'Negligent attitude'

A politically controversial measure, some politicians say it drastically worsened an already poor safety record. Trade unions argue it led to miners and their managers putting commercial considerations ahead of safety.

Ukrainian miners frequently protested over wages in the 1990s

Mining companies argue that it helped attract new investment, and prolonged the exploitation of many mines otherwise condemned to closure.

The situation in another major coal-mining region - Ukraine's Donbass - is worse.

Over the last decade, an average of 300 Ukrainian miners have died in accidents every year. The physical infrastructure of many mines is dilapidated.

In Ukraine's major coal-producing region, Donetsk, coal mines are particularly deep, and reported to be "gassy".

As in Russia, there is often a fatalistic and negligent attitude to safety.

This extends far beyond the coal industry; across the former Soviet Union, death rates in heavy industry remain high compared with global averages.

Precious metals

The third most important coal-mining region in the former Soviet Union is Kazakhstan. That country's worst mining accident took place in September last year.

More than 40 miners died at the "Lenin" mine, which belongs to Arcelor Mittal. Miners subsequently protested about what they said were low wages and poor safety standards.

Unlike the coal industry, non-fuel mining across the former Soviet Union - especially for metals such as gold and nickel - has attracted considerable foreign direct investment.

There are handsome profits to be made, and output has increased sharply over the last five years.